1 /*
2 * Copyright (c) 2008, 2020, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package java.lang.invoke;
27
28 import sun.invoke.util.BytecodeDescriptor;
29 import sun.invoke.util.VerifyAccess;
30
31 import java.lang.reflect.Constructor;
32 import java.lang.reflect.Field;
33 import java.lang.reflect.Member;
34 import java.lang.reflect.Method;
35 import java.lang.reflect.Modifier;
36 import java.util.ArrayList;
37 import java.util.Collections;
38 import java.util.Iterator;
39 import java.util.List;
40 import java.util.Objects;
41
42 import static java.lang.invoke.MethodHandleNatives.Constants.*;
43 import static java.lang.invoke.MethodHandleStatics.newIllegalArgumentException;
44 import static java.lang.invoke.MethodHandleStatics.newInternalError;
45
46 /**
47 * A {@code MemberName} is a compact symbolic datum which fully characterizes
48 * a method or field reference.
49 * A member name refers to a field, method, constructor, or member type.
50 * Every member name has a simple name (a string) and a type (either a Class or MethodType).
51 * A member name may also have a non-null declaring class, or it may be simply
52 * a naked name/type pair.
53 * A member name may also have non-zero modifier flags.
54 * Finally, a member name may be either resolved or unresolved.
55 * If it is resolved, the existence of the named member has been determined by the JVM.
56 * <p>
57 * Whether resolved or not, a member name provides no access rights or
58 * invocation capability to its possessor. It is merely a compact
59 * representation of all symbolic information necessary to link to
60 * and properly use the named member.
61 * <p>
62 * When resolved, a member name's internal implementation may include references to JVM metadata.
63 * This representation is stateless and only descriptive.
64 * It provides no private information and no capability to use the member.
65 * <p>
66 * By contrast, a {@linkplain java.lang.reflect.Method} contains fuller information
67 * about the internals of a method (except its bytecodes) and also
68 * allows invocation. A MemberName is much lighter than a Method,
69 * since it contains about 7 fields to the 16 of Method (plus its sub-arrays),
70 * and those seven fields omit much of the information in Method.
71 * @author jrose
72 */
73 /*non-public*/
74 final class ResolvedMethodName {
75 //@Injected JVM_Method* vmtarget;
76 //@Injected Class<?> vmholder;
77 };
78
79 /*non-public*/
80 final class MemberName implements Member, Cloneable {
81 private Class<?> clazz; // class in which the member is defined
82 private String name; // may be null if not yet materialized
83 private Object type; // may be null if not yet materialized
84 private int flags; // modifier bits; see reflect.Modifier
85 private ResolvedMethodName method; // cached resolved method information
86 //@Injected intptr_t vmindex; // vtable index or offset of resolved member
87 Object resolution; // if null, this guy is resolved
88
89 /** Return the declaring class of this member.
90 * In the case of a bare name and type, the declaring class will be null.
91 */
92 public Class<?> getDeclaringClass() {
93 return clazz;
94 }
95
96 /** Utility method producing the class loader of the declaring class. */
97 public ClassLoader getClassLoader() {
98 return clazz.getClassLoader();
99 }
100
101 /** Return the simple name of this member.
102 * For a type, it is the same as {@link Class#getSimpleName}.
103 * For a method or field, it is the simple name of the member.
104 * For a constructor, it is always {@code "<init>"}.
105 */
106 public String getName() {
107 if (name == null) {
108 expandFromVM();
109 if (name == null) {
110 return null;
111 }
112 }
113 return name;
114 }
115
116 public MethodType getMethodOrFieldType() {
117 if (isInvocable())
118 return getMethodType();
119 if (isGetter())
120 return MethodType.methodType(getFieldType());
121 if (isSetter())
122 return MethodType.methodType(void.class, getFieldType());
123 throw new InternalError("not a method or field: "+this);
124 }
125
126 /** Return the declared type of this member, which
127 * must be a method or constructor.
128 */
129 public MethodType getMethodType() {
130 if (type == null) {
131 expandFromVM();
132 if (type == null) {
133 return null;
134 }
135 }
136 if (!isInvocable()) {
137 throw newIllegalArgumentException("not invocable, no method type");
138 }
139
140 {
141 // Get a snapshot of type which doesn't get changed by racing threads.
142 final Object type = this.type;
143 if (type instanceof MethodType) {
144 return (MethodType) type;
145 }
146 }
147
148 // type is not a MethodType yet. Convert it thread-safely.
149 synchronized (this) {
150 if (type instanceof String sig) {
151 MethodType res = MethodType.fromDescriptor(sig, getClassLoader());
152 type = res;
153 } else if (type instanceof Object[] typeInfo) {
154 Class<?>[] ptypes = (Class<?>[]) typeInfo[1];
155 Class<?> rtype = (Class<?>) typeInfo[0];
156 MethodType res = MethodType.makeImpl(rtype, ptypes, true);
157 type = res;
158 }
159 // Make sure type is a MethodType for racing threads.
160 assert type instanceof MethodType : "bad method type " + type;
161 }
162 return (MethodType) type;
163 }
164
165 /** Return the descriptor of this member, which
166 * must be a method or constructor.
167 */
168 String getMethodDescriptor() {
169 if (type == null) {
170 expandFromVM();
171 if (type == null) {
172 return null;
173 }
174 }
175 if (!isInvocable()) {
176 throw newIllegalArgumentException("not invocable, no method type");
177 }
178
179 // Get a snapshot of type which doesn't get changed by racing threads.
180 final Object type = this.type;
181 if (type instanceof String) {
182 return (String) type;
183 } else {
184 return getMethodType().toMethodDescriptorString();
185 }
186 }
187
188 /** Return the actual type under which this method or constructor must be invoked.
189 * For non-static methods or constructors, this is the type with a leading parameter,
190 * a reference to declaring class. For static methods, it is the same as the declared type.
191 */
192 public MethodType getInvocationType() {
193 MethodType itype = getMethodOrFieldType();
194 if (isConstructor() && getReferenceKind() == REF_newInvokeSpecial)
195 return itype.changeReturnType(clazz);
196 if (!isStatic())
197 return itype.insertParameterTypes(0, clazz);
198 return itype;
199 }
200
201 /** Utility method producing the parameter types of the method type. */
202 public Class<?>[] getParameterTypes() {
203 return getMethodType().parameterArray();
204 }
205
206 /** Utility method producing the return type of the method type. */
207 public Class<?> getReturnType() {
208 return getMethodType().returnType();
209 }
210
211 /** Return the declared type of this member, which
212 * must be a field or type.
213 * If it is a type member, that type itself is returned.
214 */
215 public Class<?> getFieldType() {
216 if (type == null) {
217 expandFromVM();
218 if (type == null) {
219 return null;
220 }
221 }
222 if (isInvocable()) {
223 throw newIllegalArgumentException("not a field or nested class, no simple type");
224 }
225
226 {
227 // Get a snapshot of type which doesn't get changed by racing threads.
228 final Object type = this.type;
229 if (type instanceof Class<?>) {
230 return (Class<?>) type;
231 }
232 }
233
234 // type is not a Class yet. Convert it thread-safely.
235 synchronized (this) {
236 if (type instanceof String sig) {
237 MethodType mtype = MethodType.fromDescriptor("()"+sig, getClassLoader());
238 Class<?> res = mtype.returnType();
239 type = res;
240 }
241 // Make sure type is a Class for racing threads.
242 assert type instanceof Class<?> : "bad field type " + type;
243 }
244 return (Class<?>) type;
245 }
246
247 /** Utility method to produce either the method type or field type of this member. */
248 public Object getType() {
249 return (isInvocable() ? getMethodType() : getFieldType());
250 }
251
252 /** Utility method to produce the signature of this member,
253 * used within the class file format to describe its type.
254 */
255 public String getSignature() {
256 if (type == null) {
257 expandFromVM();
258 if (type == null) {
259 return null;
260 }
261 }
262 if (isInvocable())
263 return BytecodeDescriptor.unparse(getMethodType());
264 else
265 return BytecodeDescriptor.unparse(getFieldType());
266 }
267
268 /** Return the modifier flags of this member.
269 * @see java.lang.reflect.Modifier
270 */
271 public int getModifiers() {
272 return (flags & RECOGNIZED_MODIFIERS);
273 }
274
275 /** Return the reference kind of this member, or zero if none.
276 */
277 public byte getReferenceKind() {
278 return (byte) ((flags >>> MN_REFERENCE_KIND_SHIFT) & MN_REFERENCE_KIND_MASK);
279 }
280 private boolean referenceKindIsConsistent() {
281 byte refKind = getReferenceKind();
282 if (refKind == REF_NONE) return isType();
283 if (isField()) {
284 assert(staticIsConsistent());
285 assert(MethodHandleNatives.refKindIsField(refKind));
286 } else if (isConstructor()) {
287 assert(refKind == REF_newInvokeSpecial || refKind == REF_invokeSpecial);
288 } else if (isMethod()) {
289 assert(staticIsConsistent());
290 assert(MethodHandleNatives.refKindIsMethod(refKind));
291 if (clazz.isInterface())
292 assert(refKind == REF_invokeInterface ||
293 refKind == REF_invokeStatic ||
294 refKind == REF_invokeSpecial ||
295 refKind == REF_invokeVirtual && isObjectPublicMethod());
296 } else {
297 assert(false);
298 }
299 return true;
300 }
301 private boolean isObjectPublicMethod() {
302 if (clazz == Object.class) return true;
303 MethodType mtype = getMethodType();
304 if (name.equals("toString") && mtype.returnType() == String.class && mtype.parameterCount() == 0)
305 return true;
306 if (name.equals("hashCode") && mtype.returnType() == int.class && mtype.parameterCount() == 0)
307 return true;
308 if (name.equals("equals") && mtype.returnType() == boolean.class && mtype.parameterCount() == 1 && mtype.parameterType(0) == Object.class)
309 return true;
310 return false;
311 }
312
313 /*non-public*/
314 boolean referenceKindIsConsistentWith(int originalRefKind) {
315 int refKind = getReferenceKind();
316 if (refKind == originalRefKind) return true;
317 if (getClass().desiredAssertionStatus()) {
318 switch (originalRefKind) {
319 case REF_invokeInterface -> {
320 // Looking up an interface method, can get (e.g.) Object.hashCode
321 assert (refKind == REF_invokeVirtual || refKind == REF_invokeSpecial) : this;
322 }
323 case REF_invokeVirtual, REF_newInvokeSpecial -> {
324 // Looked up a virtual, can get (e.g.) final String.hashCode.
325 assert (refKind == REF_invokeSpecial) : this;
326 }
327 default -> {
328 assert (false) : this + " != " + MethodHandleNatives.refKindName((byte) originalRefKind);
329 }
330 }
331 }
332 return true;
333 }
334 private boolean staticIsConsistent() {
335 byte refKind = getReferenceKind();
336 return MethodHandleNatives.refKindIsStatic(refKind) == isStatic() || getModifiers() == 0;
337 }
338 private boolean vminfoIsConsistent() {
339 byte refKind = getReferenceKind();
340 assert(isResolved()); // else don't call
341 Object vminfo = MethodHandleNatives.getMemberVMInfo(this);
342 assert(vminfo instanceof Object[]);
343 long vmindex = (Long) ((Object[])vminfo)[0];
344 Object vmtarget = ((Object[])vminfo)[1];
345 if (MethodHandleNatives.refKindIsField(refKind)) {
346 assert(vmindex >= 0) : vmindex + ":" + this;
347 assert(vmtarget instanceof Class);
348 } else {
349 if (MethodHandleNatives.refKindDoesDispatch(refKind))
350 assert(vmindex >= 0) : vmindex + ":" + this;
351 else
352 assert(vmindex < 0) : vmindex;
353 assert(vmtarget instanceof MemberName) : vmtarget + " in " + this;
354 }
355 return true;
356 }
357
358 private MemberName changeReferenceKind(byte refKind, byte oldKind) {
359 assert(getReferenceKind() == oldKind);
360 assert(MethodHandleNatives.refKindIsValid(refKind));
361 flags += (((int)refKind - oldKind) << MN_REFERENCE_KIND_SHIFT);
362 return this;
363 }
364
365 private boolean testFlags(int mask, int value) {
366 return (flags & mask) == value;
367 }
368 private boolean testAllFlags(int mask) {
369 return testFlags(mask, mask);
370 }
371 private boolean testAnyFlags(int mask) {
372 return !testFlags(mask, 0);
373 }
374
375 /** Utility method to query if this member is a method handle invocation (invoke or invokeExact).
376 */
377 public boolean isMethodHandleInvoke() {
378 final int bits = MH_INVOKE_MODS &~ Modifier.PUBLIC;
379 final int negs = Modifier.STATIC;
380 if (testFlags(bits | negs, bits) &&
381 clazz == MethodHandle.class) {
382 return isMethodHandleInvokeName(name);
383 }
384 return false;
385 }
386 public static boolean isMethodHandleInvokeName(String name) {
387 switch (name) {
388 case "invoke":
389 case "invokeExact":
390 return true;
391 default:
392 return false;
393 }
394 }
395 public boolean isVarHandleMethodInvoke() {
396 final int bits = MH_INVOKE_MODS &~ Modifier.PUBLIC;
397 final int negs = Modifier.STATIC;
398 if (testFlags(bits | negs, bits) &&
399 clazz == VarHandle.class) {
400 return isVarHandleMethodInvokeName(name);
401 }
402 return false;
403 }
404 public static boolean isVarHandleMethodInvokeName(String name) {
405 try {
406 VarHandle.AccessMode.valueFromMethodName(name);
407 return true;
408 } catch (IllegalArgumentException e) {
409 return false;
410 }
411 }
412 private static final int MH_INVOKE_MODS = Modifier.NATIVE | Modifier.FINAL | Modifier.PUBLIC;
413
414 /** Utility method to query the modifier flags of this member. */
415 public boolean isStatic() {
416 return Modifier.isStatic(flags);
417 }
418 /** Utility method to query the modifier flags of this member. */
419 public boolean isPublic() {
420 return Modifier.isPublic(flags);
421 }
422 /** Utility method to query the modifier flags of this member. */
423 public boolean isPrivate() {
424 return Modifier.isPrivate(flags);
425 }
426 /** Utility method to query the modifier flags of this member. */
427 public boolean isProtected() {
428 return Modifier.isProtected(flags);
429 }
430 /** Utility method to query the modifier flags of this member. */
431 public boolean isFinal() {
432 return Modifier.isFinal(flags);
433 }
434 /** Utility method to query whether this member or its defining class is final. */
435 public boolean canBeStaticallyBound() {
436 return Modifier.isFinal(flags | clazz.getModifiers());
437 }
438 /** Utility method to query the modifier flags of this member. */
439 public boolean isVolatile() {
440 return Modifier.isVolatile(flags);
441 }
442 /** Utility method to query the modifier flags of this member. */
443 public boolean isAbstract() {
444 return Modifier.isAbstract(flags);
445 }
446 /** Utility method to query the modifier flags of this member. */
447 public boolean isNative() {
448 return Modifier.isNative(flags);
449 }
450 // let the rest (native, volatile, transient, etc.) be tested via Modifier.isFoo
451
452 // unofficial modifier flags, used by HotSpot:
453 static final int BRIDGE = 0x00000040;
454 static final int VARARGS = 0x00000080;
455 static final int SYNTHETIC = 0x00001000;
456 static final int ANNOTATION= 0x00002000;
457 static final int ENUM = 0x00004000;
458 /** Utility method to query the modifier flags of this member; returns false if the member is not a method. */
459 public boolean isBridge() {
460 return testAllFlags(IS_METHOD | BRIDGE);
461 }
462 /** Utility method to query the modifier flags of this member; returns false if the member is not a method. */
463 public boolean isVarargs() {
464 return testAllFlags(VARARGS) && isInvocable();
465 }
466 /** Utility method to query the modifier flags of this member; returns false if the member is not a method. */
467 public boolean isSynthetic() {
468 return testAllFlags(SYNTHETIC);
469 }
470
471 static final String CONSTRUCTOR_NAME = "<init>"; // the ever-popular
472
473 // modifiers exported by the JVM:
474 static final int RECOGNIZED_MODIFIERS = 0xFFFF;
475
476 // private flags, not part of RECOGNIZED_MODIFIERS:
477 static final int
478 IS_METHOD = MN_IS_METHOD, // method (not constructor)
479 IS_CONSTRUCTOR = MN_IS_CONSTRUCTOR, // constructor
480 IS_FIELD = MN_IS_FIELD, // field
481 IS_TYPE = MN_IS_TYPE, // nested type
482 CALLER_SENSITIVE = MN_CALLER_SENSITIVE, // @CallerSensitive annotation detected
483 TRUSTED_FINAL = MN_TRUSTED_FINAL; // trusted final field
484
485 static final int ALL_ACCESS = Modifier.PUBLIC | Modifier.PRIVATE | Modifier.PROTECTED;
486 static final int ALL_KINDS = IS_METHOD | IS_CONSTRUCTOR | IS_FIELD | IS_TYPE;
487 static final int IS_INVOCABLE = IS_METHOD | IS_CONSTRUCTOR;
488 static final int IS_FIELD_OR_METHOD = IS_METHOD | IS_FIELD;
489 static final int SEARCH_ALL_SUPERS = MN_SEARCH_SUPERCLASSES | MN_SEARCH_INTERFACES;
490
491 /** Utility method to query whether this member is a method or constructor. */
492 public boolean isInvocable() {
493 return testAnyFlags(IS_INVOCABLE);
494 }
495 /** Utility method to query whether this member is a method, constructor, or field. */
496 public boolean isFieldOrMethod() {
497 return testAnyFlags(IS_FIELD_OR_METHOD);
498 }
499 /** Query whether this member is a method. */
500 public boolean isMethod() {
501 return testAllFlags(IS_METHOD);
502 }
503 /** Query whether this member is a constructor. */
504 public boolean isConstructor() {
505 return testAllFlags(IS_CONSTRUCTOR);
506 }
507 /** Query whether this member is a field. */
508 public boolean isField() {
509 return testAllFlags(IS_FIELD);
510 }
511 /** Query whether this member is a type. */
512 public boolean isType() {
513 return testAllFlags(IS_TYPE);
514 }
515 /** Utility method to query whether this member is neither public, private, nor protected. */
516 public boolean isPackage() {
517 return !testAnyFlags(ALL_ACCESS);
518 }
519 /** Query whether this member has a CallerSensitive annotation. */
520 public boolean isCallerSensitive() {
521 return testAllFlags(CALLER_SENSITIVE);
522 }
523 /** Query whether this member is a trusted final field. */
524 public boolean isTrustedFinalField() { return testAllFlags(TRUSTED_FINAL|IS_FIELD); }
525
526 /** Utility method to query whether this member is accessible from a given lookup class. */
527 public boolean isAccessibleFrom(Class<?> lookupClass) {
528 int mode = (ALL_ACCESS|MethodHandles.Lookup.PACKAGE|MethodHandles.Lookup.MODULE);
529 return VerifyAccess.isMemberAccessible(this.getDeclaringClass(), this.getDeclaringClass(), flags,
530 lookupClass, null, mode);
531 }
532
533 /**
534 * Check if MemberName is a call to a method named {@code name} in class {@code declaredClass}.
535 */
536 public boolean refersTo(Class<?> declc, String n) {
537 return clazz == declc && getName().equals(n);
538 }
539
540 /** Initialize a query. It is not resolved. */
541 private void init(Class<?> defClass, String name, Object type, int flags) {
542 // defining class is allowed to be null (for a naked name/type pair)
543 //name.toString(); // null check
544 //type.equals(type); // null check
545 // fill in fields:
546 this.clazz = defClass;
547 this.name = name;
548 this.type = type;
549 this.flags = flags;
550 assert(testAnyFlags(ALL_KINDS));
551 assert(this.resolution == null); // nobody should have touched this yet
552 //assert(referenceKindIsConsistent()); // do this after resolution
553 }
554
555 /**
556 * Calls down to the VM to fill in the fields. This method is
557 * synchronized to avoid racing calls.
558 */
559 private void expandFromVM() {
560 if (type != null) {
561 return;
562 }
563 if (!isResolved()) {
564 return;
565 }
566 MethodHandleNatives.expand(this);
567 }
568
569 // Capturing information from the Core Reflection API:
570 private static int flagsMods(int flags, int mods, byte refKind) {
571 assert((flags & RECOGNIZED_MODIFIERS) == 0);
572 assert((mods & ~RECOGNIZED_MODIFIERS) == 0);
573 assert((refKind & ~MN_REFERENCE_KIND_MASK) == 0);
574 return flags | mods | (refKind << MN_REFERENCE_KIND_SHIFT);
575 }
576 /** Create a name for the given reflected method. The resulting name will be in a resolved state. */
577 public MemberName(Method m) {
578 this(m, false);
579 }
580 @SuppressWarnings("LeakingThisInConstructor")
581 public MemberName(Method m, boolean wantSpecial) {
582 Objects.requireNonNull(m);
583 // fill in vmtarget, vmindex while we have m in hand:
584 MethodHandleNatives.init(this, m);
585 if (clazz == null) { // MHN.init failed
586 if (m.getDeclaringClass() == MethodHandle.class &&
587 isMethodHandleInvokeName(m.getName())) {
588 // The JVM did not reify this signature-polymorphic instance.
589 // Need a special case here.
590 // See comments on MethodHandleNatives.linkMethod.
591 MethodType type = MethodType.methodType(m.getReturnType(), m.getParameterTypes());
592 int flags = flagsMods(IS_METHOD, m.getModifiers(), REF_invokeVirtual);
593 init(MethodHandle.class, m.getName(), type, flags);
594 if (isMethodHandleInvoke())
595 return;
596 }
597 if (m.getDeclaringClass() == VarHandle.class &&
598 isVarHandleMethodInvokeName(m.getName())) {
599 // The JVM did not reify this signature-polymorphic instance.
600 // Need a special case here.
601 // See comments on MethodHandleNatives.linkMethod.
602 MethodType type = MethodType.methodType(m.getReturnType(), m.getParameterTypes());
603 int flags = flagsMods(IS_METHOD, m.getModifiers(), REF_invokeVirtual);
604 init(VarHandle.class, m.getName(), type, flags);
605 if (isVarHandleMethodInvoke())
606 return;
607 }
608 throw new LinkageError(m.toString());
609 }
610 assert(isResolved() && this.clazz != null);
611 this.name = m.getName();
612 if (this.type == null)
613 this.type = new Object[] { m.getReturnType(), m.getParameterTypes() };
614 if (wantSpecial) {
615 if (isAbstract())
616 throw new AbstractMethodError(this.toString());
617 if (getReferenceKind() == REF_invokeVirtual)
618 changeReferenceKind(REF_invokeSpecial, REF_invokeVirtual);
619 else if (getReferenceKind() == REF_invokeInterface)
620 // invokeSpecial on a default method
621 changeReferenceKind(REF_invokeSpecial, REF_invokeInterface);
622 }
623 }
624 public MemberName asSpecial() {
625 switch (getReferenceKind()) {
626 case REF_invokeSpecial: return this;
627 case REF_invokeVirtual: return clone().changeReferenceKind(REF_invokeSpecial, REF_invokeVirtual);
628 case REF_invokeInterface: return clone().changeReferenceKind(REF_invokeSpecial, REF_invokeInterface);
629 case REF_newInvokeSpecial: return clone().changeReferenceKind(REF_invokeSpecial, REF_newInvokeSpecial);
630 }
631 throw new IllegalArgumentException(this.toString());
632 }
633 /** If this MN is not REF_newInvokeSpecial, return a clone with that ref. kind.
634 * In that case it must already be REF_invokeSpecial.
635 */
636 public MemberName asConstructor() {
637 switch (getReferenceKind()) {
638 case REF_invokeSpecial: return clone().changeReferenceKind(REF_newInvokeSpecial, REF_invokeSpecial);
639 case REF_newInvokeSpecial: return this;
640 }
641 throw new IllegalArgumentException(this.toString());
642 }
643 /** If this MN is a REF_invokeSpecial, return a clone with the "normal" kind
644 * REF_invokeVirtual; also switch either to REF_invokeInterface if clazz.isInterface.
645 * The end result is to get a fully virtualized version of the MN.
646 * (Note that resolving in the JVM will sometimes devirtualize, changing
647 * REF_invokeVirtual of a final to REF_invokeSpecial, and REF_invokeInterface
648 * in some corner cases to either of the previous two; this transform
649 * undoes that change under the assumption that it occurred.)
650 */
651 public MemberName asNormalOriginal() {
652 byte normalVirtual = clazz.isInterface() ? REF_invokeInterface : REF_invokeVirtual;
653 byte refKind = getReferenceKind();
654 byte newRefKind = refKind;
655 MemberName result = this;
656 switch (refKind) {
657 case REF_invokeInterface:
658 case REF_invokeVirtual:
659 case REF_invokeSpecial:
660 newRefKind = normalVirtual;
661 break;
662 }
663 if (newRefKind == refKind)
664 return this;
665 result = clone().changeReferenceKind(newRefKind, refKind);
666 assert(this.referenceKindIsConsistentWith(result.getReferenceKind()));
667 return result;
668 }
669 /** Create a name for the given reflected constructor. The resulting name will be in a resolved state. */
670 @SuppressWarnings("LeakingThisInConstructor")
671 public MemberName(Constructor<?> ctor) {
672 Objects.requireNonNull(ctor);
673 // fill in vmtarget, vmindex while we have ctor in hand:
674 MethodHandleNatives.init(this, ctor);
675 assert(isResolved() && this.clazz != null);
676 this.name = CONSTRUCTOR_NAME;
677 if (this.type == null)
678 this.type = new Object[] { void.class, ctor.getParameterTypes() };
679 }
680 /** Create a name for the given reflected field. The resulting name will be in a resolved state.
681 */
682 public MemberName(Field fld) {
683 this(fld, false);
684 }
685 @SuppressWarnings("LeakingThisInConstructor")
686 public MemberName(Field fld, boolean makeSetter) {
687 Objects.requireNonNull(fld);
688 // fill in vmtarget, vmindex while we have fld in hand:
689 MethodHandleNatives.init(this, fld);
690 assert(isResolved() && this.clazz != null);
691 this.name = fld.getName();
692 this.type = fld.getType();
693 assert((REF_putStatic - REF_getStatic) == (REF_putField - REF_getField));
694 byte refKind = this.getReferenceKind();
695 assert(refKind == (isStatic() ? REF_getStatic : REF_getField));
696 if (makeSetter) {
697 changeReferenceKind((byte)(refKind + (REF_putStatic - REF_getStatic)), refKind);
698 }
699 }
700 public boolean isGetter() {
701 return MethodHandleNatives.refKindIsGetter(getReferenceKind());
702 }
703 public boolean isSetter() {
704 return MethodHandleNatives.refKindIsSetter(getReferenceKind());
705 }
706 public MemberName asSetter() {
707 byte refKind = getReferenceKind();
708 assert(MethodHandleNatives.refKindIsGetter(refKind));
709 assert((REF_putStatic - REF_getStatic) == (REF_putField - REF_getField));
710 byte setterRefKind = (byte)(refKind + (REF_putField - REF_getField));
711 return clone().changeReferenceKind(setterRefKind, refKind);
712 }
713 /** Create a name for the given class. The resulting name will be in a resolved state. */
714 public MemberName(Class<?> type) {
715 init(type.getDeclaringClass(), type.getSimpleName(), type,
716 flagsMods(IS_TYPE, type.getModifiers(), REF_NONE));
717 initResolved(true);
718 }
719
720 /**
721 * Create a name for a signature-polymorphic invoker.
722 * This is a placeholder for a signature-polymorphic instance
723 * (of MH.invokeExact, etc.) that the JVM does not reify.
724 * See comments on {@link MethodHandleNatives#linkMethod}.
725 */
726 static MemberName makeMethodHandleInvoke(String name, MethodType type) {
727 return makeMethodHandleInvoke(name, type, MH_INVOKE_MODS | SYNTHETIC);
728 }
729 static MemberName makeMethodHandleInvoke(String name, MethodType type, int mods) {
730 MemberName mem = new MemberName(MethodHandle.class, name, type, REF_invokeVirtual);
731 mem.flags |= mods; // it's not resolved, but add these modifiers anyway
732 assert(mem.isMethodHandleInvoke()) : mem;
733 return mem;
734 }
735
736 static MemberName makeVarHandleMethodInvoke(String name, MethodType type) {
737 return makeVarHandleMethodInvoke(name, type, MH_INVOKE_MODS | SYNTHETIC);
738 }
739 static MemberName makeVarHandleMethodInvoke(String name, MethodType type, int mods) {
740 MemberName mem = new MemberName(VarHandle.class, name, type, REF_invokeVirtual);
741 mem.flags |= mods; // it's not resolved, but add these modifiers anyway
742 assert(mem.isVarHandleMethodInvoke()) : mem;
743 return mem;
744 }
745
746 // bare-bones constructor; the JVM will fill it in
747 MemberName() { }
748
749 // locally useful cloner
750 @Override protected MemberName clone() {
751 try {
752 return (MemberName) super.clone();
753 } catch (CloneNotSupportedException ex) {
754 throw newInternalError(ex);
755 }
756 }
757
758 /** Get the definition of this member name.
759 * This may be in a super-class of the declaring class of this member.
760 */
761 public MemberName getDefinition() {
762 if (!isResolved()) throw new IllegalStateException("must be resolved: "+this);
763 if (isType()) return this;
764 MemberName res = this.clone();
765 res.clazz = null;
766 res.type = null;
767 res.name = null;
768 res.resolution = res;
769 res.expandFromVM();
770 assert(res.getName().equals(this.getName()));
771 return res;
772 }
773
774 @Override
775 @SuppressWarnings({"deprecation", "removal"})
776 public int hashCode() {
777 // Avoid autoboxing getReferenceKind(), since this is used early and will force
778 // early initialization of Byte$ByteCache
779 return Objects.hash(clazz, new Byte(getReferenceKind()), name, getType());
780 }
781
782 @Override
783 public boolean equals(Object that) {
784 return (that instanceof MemberName && this.equals((MemberName)that));
785 }
786
787 /** Decide if two member names have exactly the same symbolic content.
788 * Does not take into account any actual class members, so even if
789 * two member names resolve to the same actual member, they may
790 * be distinct references.
791 */
792 public boolean equals(MemberName that) {
793 if (this == that) return true;
794 if (that == null) return false;
795 return this.clazz == that.clazz
796 && this.getReferenceKind() == that.getReferenceKind()
797 && Objects.equals(this.name, that.name)
798 && Objects.equals(this.getType(), that.getType());
799 }
800
801 // Construction from symbolic parts, for queries:
802 /** Create a field or type name from the given components:
803 * Declaring class, name, type, reference kind.
804 * The declaring class may be supplied as null if this is to be a bare name and type.
805 * The resulting name will in an unresolved state.
806 */
807 public MemberName(Class<?> defClass, String name, Class<?> type, byte refKind) {
808 init(defClass, name, type, flagsMods(IS_FIELD, 0, refKind));
809 initResolved(false);
810 }
811 /** Create a method or constructor name from the given components:
812 * Declaring class, name, type, reference kind.
813 * It will be a constructor if and only if the name is {@code "<init>"}.
814 * The declaring class may be supplied as null if this is to be a bare name and type.
815 * The last argument is optional, a boolean which requests REF_invokeSpecial.
816 * The resulting name will in an unresolved state.
817 */
818 public MemberName(Class<?> defClass, String name, MethodType type, byte refKind) {
819 int initFlags = (name != null && name.equals(CONSTRUCTOR_NAME) ? IS_CONSTRUCTOR : IS_METHOD);
820 init(defClass, name, type, flagsMods(initFlags, 0, refKind));
821 initResolved(false);
822 }
823 /** Create a method, constructor, or field name from the given components:
824 * Reference kind, declaring class, name, type.
825 */
826 public MemberName(byte refKind, Class<?> defClass, String name, Object type) {
827 int kindFlags;
828 if (MethodHandleNatives.refKindIsField(refKind)) {
829 kindFlags = IS_FIELD;
830 if (!(type instanceof Class))
831 throw newIllegalArgumentException("not a field type");
832 } else if (MethodHandleNatives.refKindIsMethod(refKind)) {
833 kindFlags = IS_METHOD;
834 if (!(type instanceof MethodType))
835 throw newIllegalArgumentException("not a method type");
836 } else if (refKind == REF_newInvokeSpecial) {
837 kindFlags = IS_CONSTRUCTOR;
838 if (!(type instanceof MethodType) ||
839 !CONSTRUCTOR_NAME.equals(name))
840 throw newIllegalArgumentException("not a constructor type or name");
841 } else {
842 throw newIllegalArgumentException("bad reference kind "+refKind);
843 }
844 init(defClass, name, type, flagsMods(kindFlags, 0, refKind));
845 initResolved(false);
846 }
847 /** Query whether this member name is resolved to a non-static, non-final method.
848 */
849 public boolean hasReceiverTypeDispatch() {
850 return MethodHandleNatives.refKindDoesDispatch(getReferenceKind());
851 }
852
853 /** Query whether this member name is resolved.
854 * A resolved member name is one for which the JVM has found
855 * a method, constructor, field, or type binding corresponding exactly to the name.
856 * (Document?)
857 */
858 public boolean isResolved() {
859 return resolution == null;
860 }
861
862 void initResolved(boolean isResolved) {
863 assert(this.resolution == null); // not initialized yet!
864 if (!isResolved)
865 this.resolution = this;
866 assert(isResolved() == isResolved);
867 }
868
869 void checkForTypeAlias(Class<?> refc) {
870 if (isInvocable()) {
871 MethodType type;
872 if (this.type instanceof MethodType)
873 type = (MethodType) this.type;
874 else
875 this.type = type = getMethodType();
876 if (type.erase() == type) return;
877 if (VerifyAccess.isTypeVisible(type, refc)) return;
878 throw new LinkageError("bad method type alias: "+type+" not visible from "+refc);
879 } else {
880 Class<?> type;
881 if (this.type instanceof Class<?>)
882 type = (Class<?>) this.type;
883 else
884 this.type = type = getFieldType();
885 if (VerifyAccess.isTypeVisible(type, refc)) return;
886 throw new LinkageError("bad field type alias: "+type+" not visible from "+refc);
887 }
888 }
889
890
891 /** Produce a string form of this member name.
892 * For types, it is simply the type's own string (as reported by {@code toString}).
893 * For fields, it is {@code "DeclaringClass.name/type"}.
894 * For methods and constructors, it is {@code "DeclaringClass.name(ptype...)rtype"}.
895 * If the declaring class is null, the prefix {@code "DeclaringClass."} is omitted.
896 * If the member is unresolved, a prefix {@code "*."} is prepended.
897 */
898 @SuppressWarnings("LocalVariableHidesMemberVariable")
899 @Override
900 public String toString() {
901 if (isType())
902 return type.toString(); // class java.lang.String
903 // else it is a field, method, or constructor
904 StringBuilder buf = new StringBuilder();
905 if (getDeclaringClass() != null) {
906 buf.append(getName(clazz));
907 buf.append('.');
908 }
909 String name = this.name; // avoid expanding from VM
910 buf.append(name == null ? "*" : name);
911 Object type = this.type; // avoid expanding from VM
912 if (!isInvocable()) {
913 buf.append('/');
914 buf.append(type == null ? "*" : getName(type));
915 } else {
916 buf.append(type == null ? "(*)*" : getName(type));
917 }
918 byte refKind = getReferenceKind();
919 if (refKind != REF_NONE) {
920 buf.append('/');
921 buf.append(MethodHandleNatives.refKindName(refKind));
922 }
923 //buf.append("#").append(System.identityHashCode(this));
924 return buf.toString();
925 }
926 private static String getName(Object obj) {
927 if (obj instanceof Class<?>)
928 return ((Class<?>)obj).getName();
929 return String.valueOf(obj);
930 }
931
932 public IllegalAccessException makeAccessException(String message, Object from) {
933 message = message + ": "+ toString();
934 if (from != null) {
935 if (from == MethodHandles.publicLookup()) {
936 message += ", from public Lookup";
937 } else {
938 Module m;
939 Class<?> plc;
940 if (from instanceof MethodHandles.Lookup lookup) {
941 from = lookup.lookupClass();
942 m = lookup.lookupClass().getModule();
943 plc = lookup.previousLookupClass();
944 } else {
945 m = ((Class<?>)from).getModule();
946 plc = null;
947 }
948 message += ", from " + from + " (" + m + ")";
949 if (plc != null) {
950 message += ", previous lookup " +
951 plc.getName() + " (" + plc.getModule() + ")";
952 }
953 }
954 }
955 return new IllegalAccessException(message);
956 }
957 private String message() {
958 if (isResolved())
959 return "no access";
960 else if (isConstructor())
961 return "no such constructor";
962 else if (isMethod())
963 return "no such method";
964 else
965 return "no such field";
966 }
967 public ReflectiveOperationException makeAccessException() {
968 String message = message() + ": "+ toString();
969 ReflectiveOperationException ex;
970 if (isResolved() || !(resolution instanceof NoSuchMethodError ||
971 resolution instanceof NoSuchFieldError))
972 ex = new IllegalAccessException(message);
973 else if (isConstructor())
974 ex = new NoSuchMethodException(message);
975 else if (isMethod())
976 ex = new NoSuchMethodException(message);
977 else
978 ex = new NoSuchFieldException(message);
979 if (resolution instanceof Throwable)
980 ex.initCause((Throwable) resolution);
981 return ex;
982 }
983
984 /** Actually making a query requires an access check. */
985 /*non-public*/
986 static Factory getFactory() {
987 return Factory.INSTANCE;
988 }
989 /** A factory type for resolving member names with the help of the VM.
990 * TBD: Define access-safe public constructors for this factory.
991 */
992 /*non-public*/
993 static class Factory {
994 private Factory() { } // singleton pattern
995 static Factory INSTANCE = new Factory();
996
997 private static int ALLOWED_FLAGS = ALL_KINDS;
998
999 /// Queries
1000 List<MemberName> getMembers(Class<?> defc,
1001 String matchName, Object matchType,
1002 int matchFlags, Class<?> lookupClass) {
1003 matchFlags &= ALLOWED_FLAGS;
1004 String matchSig = null;
1005 if (matchType != null) {
1006 matchSig = BytecodeDescriptor.unparse(matchType);
1007 if (matchSig.startsWith("("))
1008 matchFlags &= ~(ALL_KINDS & ~IS_INVOCABLE);
1009 else
1010 matchFlags &= ~(ALL_KINDS & ~IS_FIELD);
1011 }
1012 final int BUF_MAX = 0x2000;
1013 int len1 = matchName == null ? 10 : matchType == null ? 4 : 1;
1014 MemberName[] buf = newMemberBuffer(len1);
1015 int totalCount = 0;
1016 ArrayList<MemberName[]> bufs = null;
1017 int bufCount = 0;
1018 for (;;) {
1019 bufCount = MethodHandleNatives.getMembers(defc,
1020 matchName, matchSig, matchFlags,
1021 lookupClass,
1022 totalCount, buf);
1023 if (bufCount <= buf.length) {
1024 if (bufCount < 0) bufCount = 0;
1025 totalCount += bufCount;
1026 break;
1027 }
1028 // JVM returned to us with an intentional overflow!
1029 totalCount += buf.length;
1030 int excess = bufCount - buf.length;
1031 if (bufs == null) bufs = new ArrayList<>(1);
1032 bufs.add(buf);
1033 int len2 = buf.length;
1034 len2 = Math.max(len2, excess);
1035 len2 = Math.max(len2, totalCount / 4);
1036 buf = newMemberBuffer(Math.min(BUF_MAX, len2));
1037 }
1038 ArrayList<MemberName> result = new ArrayList<>(totalCount);
1039 if (bufs != null) {
1040 for (MemberName[] buf0 : bufs) {
1041 Collections.addAll(result, buf0);
1042 }
1043 }
1044 for (int i = 0; i < bufCount; i++) {
1045 result.add(buf[i]);
1046 }
1047 // Signature matching is not the same as type matching, since
1048 // one signature might correspond to several types.
1049 // So if matchType is a Class or MethodType, refilter the results.
1050 if (matchType != null && matchType != matchSig) {
1051 for (Iterator<MemberName> it = result.iterator(); it.hasNext();) {
1052 MemberName m = it.next();
1053 if (!matchType.equals(m.getType()))
1054 it.remove();
1055 }
1056 }
1057 return result;
1058 }
1059 /** Produce a resolved version of the given member.
1060 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1061 * Access checking is performed on behalf of the given {@code lookupClass}.
1062 * If lookup fails or access is not permitted, null is returned.
1063 * Otherwise a fresh copy of the given member is returned, with modifier bits filled in.
1064 */
1065 private MemberName resolve(byte refKind, MemberName ref, Class<?> lookupClass, int allowedModes,
1066 boolean speculativeResolve) {
1067 MemberName m = ref.clone(); // JVM will side-effect the ref
1068 assert(refKind == m.getReferenceKind());
1069 try {
1070 // There are 4 entities in play here:
1071 // * LC: lookupClass
1072 // * REFC: symbolic reference class (MN.clazz before resolution);
1073 // * DEFC: resolved method holder (MN.clazz after resolution);
1074 // * PTYPES: parameter types (MN.type)
1075 //
1076 // What we care about when resolving a MemberName is consistency between DEFC and PTYPES.
1077 // We do type alias (TA) checks on DEFC to ensure that. DEFC is not known until the JVM
1078 // finishes the resolution, so do TA checks right after MHN.resolve() is over.
1079 //
1080 // All parameters passed by a caller are checked against MH type (PTYPES) on every invocation,
1081 // so it is safe to call a MH from any context.
1082 //
1083 // REFC view on PTYPES doesn't matter, since it is used only as a starting point for resolution and doesn't
1084 // participate in method selection.
1085 m = MethodHandleNatives.resolve(m, lookupClass, allowedModes, speculativeResolve);
1086 if (m == null && speculativeResolve) {
1087 return null;
1088 }
1089 m.checkForTypeAlias(m.getDeclaringClass());
1090 m.resolution = null;
1091 } catch (ClassNotFoundException | LinkageError ex) {
1092 // JVM reports that the "bytecode behavior" would get an error
1093 assert(!m.isResolved());
1094 m.resolution = ex;
1095 return m;
1096 }
1097 assert(m.referenceKindIsConsistent());
1098 m.initResolved(true);
1099 assert(m.vminfoIsConsistent());
1100 return m;
1101 }
1102 /** Produce a resolved version of the given member.
1103 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1104 * Access checking is performed on behalf of the given {@code lookupClass}.
1105 * If lookup fails or access is not permitted, a {@linkplain ReflectiveOperationException} is thrown.
1106 * Otherwise a fresh copy of the given member is returned, with modifier bits filled in.
1107 */
1108 public <NoSuchMemberException extends ReflectiveOperationException>
1109 MemberName resolveOrFail(byte refKind, MemberName m,
1110 Class<?> lookupClass, int allowedModes,
1111 Class<NoSuchMemberException> nsmClass)
1112 throws IllegalAccessException, NoSuchMemberException {
1113 assert lookupClass != null || allowedModes == LM_TRUSTED;
1114 MemberName result = resolve(refKind, m, lookupClass, allowedModes, false);
1115 if (result.isResolved())
1116 return result;
1117 ReflectiveOperationException ex = result.makeAccessException();
1118 if (ex instanceof IllegalAccessException) throw (IllegalAccessException) ex;
1119 throw nsmClass.cast(ex);
1120 }
1121 /** Produce a resolved version of the given member.
1122 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1123 * Access checking is performed on behalf of the given {@code lookupClass}.
1124 * If lookup fails or access is not permitted, return null.
1125 * Otherwise a fresh copy of the given member is returned, with modifier bits filled in.
1126 */
1127 public MemberName resolveOrNull(byte refKind, MemberName m, Class<?> lookupClass, int allowedModes) {
1128 assert lookupClass != null || allowedModes == LM_TRUSTED;
1129 MemberName result = resolve(refKind, m, lookupClass, allowedModes, true);
1130 if (result != null && result.isResolved())
1131 return result;
1132 return null;
1133 }
1134 /** Return a list of all methods defined by the given class.
1135 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1136 * Access checking is performed on behalf of the given {@code lookupClass}.
1137 * Inaccessible members are not added to the last.
1138 */
1139 public List<MemberName> getMethods(Class<?> defc, boolean searchSupers,
1140 Class<?> lookupClass) {
1141 return getMethods(defc, searchSupers, null, null, lookupClass);
1142 }
1143 /** Return a list of matching methods defined by the given class.
1144 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1145 * Returned methods will match the name (if not null) and the type (if not null).
1146 * Access checking is performed on behalf of the given {@code lookupClass}.
1147 * Inaccessible members are not added to the last.
1148 */
1149 public List<MemberName> getMethods(Class<?> defc, boolean searchSupers,
1150 String name, MethodType type, Class<?> lookupClass) {
1151 int matchFlags = IS_METHOD | (searchSupers ? SEARCH_ALL_SUPERS : 0);
1152 return getMembers(defc, name, type, matchFlags, lookupClass);
1153 }
1154 /** Return a list of all constructors defined by the given class.
1155 * Access checking is performed on behalf of the given {@code lookupClass}.
1156 * Inaccessible members are not added to the last.
1157 */
1158 public List<MemberName> getConstructors(Class<?> defc, Class<?> lookupClass) {
1159 return getMembers(defc, null, null, IS_CONSTRUCTOR, lookupClass);
1160 }
1161 /** Return a list of all fields defined by the given class.
1162 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1163 * Access checking is performed on behalf of the given {@code lookupClass}.
1164 * Inaccessible members are not added to the last.
1165 */
1166 public List<MemberName> getFields(Class<?> defc, boolean searchSupers,
1167 Class<?> lookupClass) {
1168 return getFields(defc, searchSupers, null, null, lookupClass);
1169 }
1170 /** Return a list of all fields defined by the given class.
1171 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1172 * Returned fields will match the name (if not null) and the type (if not null).
1173 * Access checking is performed on behalf of the given {@code lookupClass}.
1174 * Inaccessible members are not added to the last.
1175 */
1176 public List<MemberName> getFields(Class<?> defc, boolean searchSupers,
1177 String name, Class<?> type, Class<?> lookupClass) {
1178 int matchFlags = IS_FIELD | (searchSupers ? SEARCH_ALL_SUPERS : 0);
1179 return getMembers(defc, name, type, matchFlags, lookupClass);
1180 }
1181 /** Return a list of all nested types defined by the given class.
1182 * Super types are searched (for inherited members) if {@code searchSupers} is true.
1183 * Access checking is performed on behalf of the given {@code lookupClass}.
1184 * Inaccessible members are not added to the last.
1185 */
1186 public List<MemberName> getNestedTypes(Class<?> defc, boolean searchSupers,
1187 Class<?> lookupClass) {
1188 int matchFlags = IS_TYPE | (searchSupers ? SEARCH_ALL_SUPERS : 0);
1189 return getMembers(defc, null, null, matchFlags, lookupClass);
1190 }
1191 private static MemberName[] newMemberBuffer(int length) {
1192 MemberName[] buf = new MemberName[length];
1193 // fill the buffer with dummy structs for the JVM to fill in
1194 for (int i = 0; i < length; i++)
1195 buf[i] = new MemberName();
1196 return buf;
1197 }
1198 }
1199 }